Hearing loss occurs along a broad continuum ranging in degree from slight to profound. Individuals with severe and profound hearing loss generally are characterized as deaf, whereas individuals with lesser degrees of impairment, including those with unilateral hearing loss (i.e., involving only one ear), are characterized as hard of hearing. Childhood hearing loss of any type and degree, if unmanaged, is likely to have a negative impact on the development of spoken and receptive language, the ability to read and write, and academic achievement. For example, a 1998 study of 1,218 children with minimal hearing loss showed that 37 percent had failed a grade. Similarly, studies have shown that children with unilateral hearing loss are ten times more likely than normally hearing children to fail a grade. The vast majority (94–96%) of children with hearing loss are hard of hearing rather than deaf. For these children, speech may be audible (i.e., detectable) but not intelligible enough to allow them to hear one word as distinct from another.

There are approximately 50,000 school-age deaf children in the United States, a figure representing a dramatic decline since the early 1970s. An additional 5 million school-age children are permanently hard of hearing and at educational risk. An estimated 1.5 million more suffer from conductive, usually temporary, hearing loss. Inclusion of preschool children could put the total number of children with hearing loss close to 10 million.

Historically, approaches to educating children who are deaf have been based on emotion and personal philosophy rather than positive outcome; in contrast, the education of children who are hard of hearing has largely been ignored. Educational practices in the United States can be linked directly to the teachings of European educators active during the eighteenth and nineteenth centuries. Of note, in 1770 French cleric Charles-Michel de l'Épée founded a school in which he emphasized the use of sign language and finger spelling (i.e., a manual approach). Around the same time, schools were established in England by members of the Braidwood family, who emphasized the use of spoken language and speechreading without sign language (i.e., an oral approach).

In the United States, the father of Alice Cogswell, who lost her hearing at an early age, commissioned Thomas Hopkins Gallaudet to travel to Europe and learn methods for teaching deaf children. Refused help by the Braidwoods, Gallaudet learned de l'Épée's manual method. In 1817 Gallaudet opened a school in the United States based on the manual approach (now the American School for the Deaf). Gallaudet's son became president of the first college for deaf students in the United States, now known as Gallaudet University.

Oralism took root years later when another young girl from a prominent family, Mabel Hubbard, lost her hearing. In 1867 her father helped establish an oral school. As an adult, Hubbard married Alexander Graham Bell, who became a passionate advocate for oralism. During the late nineteenth century, Bell and Gallaudet often engaged in debate about the merits of the oral and manual approaches. The debate would continue well into the twentieth century.

Children in the United States who are deaf or hard of hearing are legally entitled to a free and appropriate education. Federal law requires a continuum of educational options, ranging from placement in a self-contained classroom with other children who are deaf to full-time placement in a regular education classroom with normally hearing peers. Most often, the placement involves a variation or a combination of the two extremes. An alternative placement is attendance at a residential school, in which the child can participate fully in the deaf culture.

Perhaps the most important educational decision is the communication method that will be used. The choice lies with the parents, and the best decision is specific to each child and family. Most children who are deaf use one or some combination of three communication modes: American Sign Language, a manual language that is distinctly different from English (i.e., a person does not sign and speak at the same time); a system of manually coded English (i.e., a signed version of English); or hearing and spoken language. A relatively smaller number of children use Cued Speech, a system in which hand gestures enhance speechreading.

Children with hearing loss require support services in order to benefit maximally from a free and appropriate education. For example, it is essential that they receive services from an audiologist, including management of their hearing aids, classroom listening devices, and listening environments. Poor listening conditions can render a hard of hearing child functionally deaf.

The education of children who are deaf will be revolutionized by two dramatic changes. First, legally mandated neonatal hearing-screening programs are changing the average age at identification from approximately three years to approximately three months. Research has shown that when appropriate hearing aids and early intervention are in place by six months of age, a child is likely to have age-normal language and learning milestones at kindergarten entry. In this light, the most important educational years are the child's very first years, when the family participates in parent–infant programming. Second, cochlear implants are being made available to increasingly younger children. These surgically implanted devices convert sound into electrical current, which then bypasses much of the hearing mechanism to stimulate surviving nerve elements directly. The coded electrical current creates sensations, which the brain, with considerable listening training, can learn to interpret as sound. Research suggests that children who use cochlear implants surpass children with similar degrees of hearing loss who use hearing aids in the areas of speech recognition, speech production, language content and form, and reading.

Children who benefit from early intervention and improved hearing technology, including cochlear implants, are likely to enter kindergarten ready for the educational mainstream. In the absence of additional disabilities, and with appropriate support services, it is possible that these children may never require special education placements and will choose to use sign language only if it is their cultural preference.